2002 plastic window prevent scratch and cracks
 

I have a 2002 Boxster I was told to put a towel over the rear window when folding it down to protect from scratching and cracking.

Is there any aftermarket towels with straps on them covering the window?

I would try doing a search for it, I have been reading posts on here for a few months and do not recall anyone mentioning using a towel to protect the plastic window. I do not see how that would keep it from cracking but I may have missed it. I have seen where some have either changed the plastic window for a glass one or replaced the entire top with an aftermarket one with a glass window.

Throw in towel
 

reposted cuz I can't type

Throw in the towel
 

What they are refering to is a technique to help prevent the plastic window from cracking where it is folded in the middle. What you do is place a rolled up towel in the fold of the window as it is retracting to keep the window from bending too sharply as it is folding up. If you are by yourself, it requires that you partiallly retract the top, get out and place the rolled up towel in the fold of the window, then get back in and continue with the top retracting. it makes the window fold around the towel in a nice round bend, instead of a sharp bend. I store the rolled up towel behind the roll bar in my car. I got a dark grey towel and you can hardly see it with my black interior. It sounds like a PITA, but is better than cracking the window in two. ($$$$$)
BTW, don't try to put the top down if the weather is cold. You are taking a risk of cracking the window along the fold line because the plastic window is less flexible when it is cold.

The instructions for installing the hard top include putting a piece of felt over the window. That way the plastic won't rub against itself for the 3-4 months that the top is in the open position.

I bought a used hard top cover and the seller threw in the official Porsche felt and a storage bag. Previously, I used a piece of felt from a fabric store and it functioned just as well.

For keeping the window from scratching, probably the single most important thing is to make sure their is no dirt or dust on the window before you put the top down, and never wipe a plastic window with a dry cloth.
I carry a plant spray bottle with water and a soft towel in the trunks of my two convertibles with plastic windows. I spray the window and wipe it clean every time before putting the top down and I've had Triumphs for over 25 years with no scratches in the windows this way.
Even when clean, if the window folds so the plastic is rubbing against itself, it will leave a mark. Felt or soft towels on the windows works really well to protect them, but you still want to make sure they are free of dust or they could still get scratched.

Another thing you can do
 

to keep the rear window from cracking is to keep the plastic itself flexible by using something that restores the oils in it. I use Novus #1 twice a year on mine and it keeps the plastic clear and flexible. I also try to keep it inside and or covered when I can to reduce the drying effect of the sun's rays.

Novus sells a kit consisting of three grades of plastic cleaners #1, #2 and #3. When I bought my car, the window was yellowed and had a crusty surface feeling to it. One polish with #3 and one with #2 and it was beginning to look clear. #1 brought it to the clear and shiny and soft feeling stage. I use #1 just to keep it that way as #3 and #2 are abrasive and good for correcting, not for maintaining.

But whatever you do, don't raise or lower the window in the cold. If it is in the 60s or 50s and the car hasn't been sitting in the sun so the plastic can warm up, I even lower or raise it in stages and even get out and make sure it is folding nicely if I'm lowering it ("the chop" it is called because it is done with the side of the arm). In the 40s or below, the top doesn't ever get raised or lowered. If I had to, I'd use a space heater inside the car to warm the plastic before even moving the top at those temps.

The towel or felt is good for not having the plastic rub against itself and dig whatever dirt is on it into the plastic surface.

I understand the towel now, thanks for explaining it even if it does not effect me as I have a glass window. I enjoy learning new things about Boxsters of all years.